insidious

adjective

Definition of insidiousnext
as in treacherous
formal causing harm in a way that is gradual or not easily noticed Most people with this insidious disease have no idea that they are infected. an insidious enemy

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Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Recent Examples of insidious But there’s a historical, and some might argue insidious, irony to all of this. — Drew Pittock, USA Today, 25 July 2026 But, as Ellis demonstrates in this survey of the city’s racial history, liberal policy achievements tend to obscure more insidious forms of exclusion. — The New Yorker, New Yorker, 20 July 2026 Beneath all the splendor, the couture, the balls, and the opera lurked an undercurrent of hatred, one that would fester and erupt in ways both insidious and catastrophic. — Literary Hub, 17 July 2026 But this last year, in particular, has broken new, insidious ground. — Los Angeles Times, 16 July 2026 See All Example Sentences for insidious
Recent Examples of Synonyms for insidious
  1. treacherous
  2. subtle
  3. false
  4. deceptive
  5. perfidious
  6. incorrect
  7. wrong
Adjective
  • When planning paths and features, follow the contour of the slope rather than going straight up and down to slow water and create less treacherous access.
    — Mary Marlowe Leverette, Southern Living, 11 Aug. 2026
  • The Hand of the Queen will have a treacherous road ahead, especially with the increasingly dictatorial Queen Rhaenyra (Emma D'Arcy), who was in no big rush to save Corlys from Ormund's clutches.
    — Bryan Alexander, USA Today, 10 Aug. 2026
Definition of treacherous
Adjective
  • Her lyrics, like those of many of her biggest musical influences, are dense texts, full of winking allusions and subtle references to records, bands, and albums that have shaped her own songwriting.
    — Jonathan Bernstein, Rolling Stone, 14 Aug. 2026
  • Izquierdo recommends asking for softly disconnected layers, a blended curtain fringe, and soft, subtle texture.
    — Loren Savini, Allure, 14 Aug. 2026
Definition of subtle
Adjective
  • Along with the WiFi jammer, deputies said they were found to be in possession of false license plates and burglary tools.
    — Dean Fioresi, CBS News, 13 Aug. 2026
  • Many of these times, KFA employees allegedly filed false expense reports chalking up the charges to meals, drinks, or standard massages.
    — Jessie Yeung, CNN Money, 12 Aug. 2026
Definition of false
Adjective
  • Violations of the law are a deceptive trade practice, which can be investigated by the state attorney general's office.
    — Seth Klamann, Denver Post, 12 Aug. 2026
  • Protection of the president has often required deft and deceptive tactics by the Secret Service.
    — Donald J. Mihalek, ABC News, 11 Aug. 2026
Definition of deceptive
Adjective
  • Logan Marshall-Green as Melanthius Melanthius is a perfidious goatherd who sides with Antinous.
    — Hannah Abraham, Forbes.com, 18 July 2026
  • This is perhaps the most perfidious practice of this sort of politics.
    — David M. Drucker, Twin Cities, 3 June 2026
Definition of perfidious
Adjective
  • The fact that the scoreboard was incorrect, Guccione told a pool reporter after the game, does not play a part in the ruling.
    — Mitch Bannon, New York Times, 11 Aug. 2026
  • The counterweight to that allure is emotional intelligence, the instinct to notice when the numbers are accurate, but the feeling is incorrect.
    — Olatunde Badmus, Forbes.com, 7 Aug. 2026
Definition of incorrect
Adjective
  • The company’s investment in the hedge fund, as well as wrong-way bets in Asian equity markets, drove part of the losses, said the person, who asked not to be identified citing private details.
    — Katherine Doherty, Fortune, 15 Aug. 2026
  • Maybe in this new era, more things will go right than wrong for the Mets.
    — Abbey Mastracco, New York Daily News, 15 Aug. 2026
Definition of wrong

Browse Nearby Words

inside tracks
insidious
insidiously
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Cite this Entry

“Insidious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/insidious. Accessed 16 Aug. 2026.

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Nglish: Translation of insidious for Spanish Speakers

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